Process for breaking petroleum emulsions



United States Patent 2,685,886 Patented Nov. 30, 1854 PROCESS FOR BREAKING PETROLEUM EMULSIONS Melvin De Groote, University City, Mo, assignor to Petrolite Corporation, a corporation of Delaware No Drawing. Application January 21, 1952, Serial No. 267,517

12 Claims. (Cl. 252342) This invention relates to processes of procedures particularly adapted for preventing, breaking or resolving emulsions of the water-in-oil type, and particularly petroleum emulsions.

Complementary to the above aspect of my invention is my companion invention concerned with the new chemical products or compounds used as the demulsifying agents in said aforementioned processes or procedures, as well as the application of such chemical compounds, products and the like, in various other arts and industries, along with the method for manufacturing said new chemical products or compounds which are of outstanding value in demulsification. See my co-pending application, Serial No. 267,518, filed January 21, 1952.

My invention provides an economical and rapid process for resolving petroleum emulsions of the water-in-oil type, that are commonly referred to as cut oil, roily oil, emulsified oil, etc., and which comprise fine droplets of naturally-occurring waters or brines dispersed in a more or less permanent state throughout the oil which constitutes the continuous phase of the emulsion.

It also provides an economical and rapid process for separating emulsions which have been prepared under controlled conditions from mineral oil, such as crude oil and relatively soft waters or weak brines. Controlled emulsification and subsequent demulsification under the conditions just mentioned are of significant value in removing impurities, particularly inorganic salts, from pipeline oil.

The demulsifying agents employed in the present process are fractional esters obtained from a polycarboxy acid or the equivalent and derivatives obtained in turn by the oxypropylation of acyl phenol monosulfides of the general formula 0 OH HO 0 in which R1 and R2 are alkyl groups having 1 to 20 carbon atoms and R3 and R4 are members of the group consisting of alkyl, aryl, alkoxyalkyl, aroxyalkyl, aralkyl, alkaryl and cycloalkyl radicals. Such acyl phenol monosuifide is treated with propylene oxide so the molecular weight based on the hydroxyl value is within the range of 1000 to approximately 7000. Such oxypropylation derivatives are invariably xylene-soluble, and waterinsoluble. When the molecular weight based on the hydroxyl value is in the neighborhood of 1,000 or thereabouts the oxypropylation product is almost invariably kerosene-soluble. In fact, depending on the particular acyl phenol monosulfide subjected to oxypropylation, the product may become kerosene-soluble at a lower range, for instance, 700 or 800 molecular weight.

The most satisfactory monosulfides suitable as initial reactants are preferably those in which the acyl radical is derived from a detergent-forming acid selected from the group of higher fatty acids and resinic acids, such as abietic acid and naphthenic acids. The detergent-forming monocarboxy acids have at least 8 and not over 22 carbon atoms. Satisfactory monosulfides suitable as initial reactants also may contain acyl radicals derived from a lower fatty acid. The expression lower fatty acids refers to those having less than 8 carbon atoms. The most suitable phenols for conversion into the monosulfides are substituted phenols in which the hydrocarbon substituent has at least 4 carbon atoms and not over 14 carbon atoms.

These acyl phenol monosulfides which are subjected to oxypropylation prior to esterification may be obtained substituent is in the meta position.

by Well known methods. Their preparation is described, for example, in U. S. Patent No. 2,319,662, dated May 18, 1943, to Cook et a1. My preference is to use acyl phenol monosulfides in which R1 and R2 are the same and have 4 to 16 carbon atoms, i. e., are derivatives of butylphenol, amylphenol, nonylphenol, decylphenol, dodecylphenol, cardanol and hydrogenated cardanol. Obviously, the substituent need not be limited to the para position, but this appears preferable. Indeed, when derived from cardanol or hydrogenated cardonal the Ortho-substituted amyl or butyl phenol may be used very satisfactorily. It is my preference to use materials in which the acyl radical is the same and is derived from a higher fatty acid having 8 to 18 carbon atoms although excellent results have been obtained when derived from various naphthenic acids.

Purely as a matter of convenience the acyl phenol nfionosulfides previously described may be represented t us:

For convenience, then, the oxypropylated derivative may be represented by the following formula:

R'O(O3H O),,H

ll l lO (canton cam 0 011),."

in which the characters have their previous significance and n" is a whole number not over 2, and R is the radical of the polycarboxy acid (COOH),,- and preferably free from any radicals having more than 8 uninterrupted carbon atoms in a single group, and with the further proviso that the parent diol prior to esterification be preferably xylene-soluble, and better still, kerosene-soluble. The diols herein employed as raw materials are water-insoluble.

Attention is directed to U. S. Patent No. 2,562,878, dated August 7, 1951, in which there is described, among other things, a process for breaking petroleum emulsions of the water-in-oil type characterized by subjecting the emulsion to the action of an esterification product of a dicarboxylic acid and a polyalkylene glycol, in which the ratio of equivalents of polybasic acid to equivalents of polyalkylene glycol is in the range of 0.5 to 2.0, in which the alkylene group has from 2 to 3 carbon atoms, and in which the molecular weight of the product is between 1,500 to 4,000.

In the instant case the initial starting materials, i. e., acyl phenol monosulfides as previously described, are Water-insoluble.

Numerous water-insoluble compounds susceptible to oxyalkylation, and particularly to oxyethylation, have been oxyethylated so as to produce effective surfaceactive agents, which, in some instances at least, also have had at least modest demulsifying property. Reference is made to similar monomeric compounds having a hydrophobe group containing, for example, 8 to 32 carbon atoms, and a reactive hydrogen atom, such as the usual acids, alcohols, alkylated phenols, amines, amides, etc. In such instances, invariably the approach was to introduce a counter-balancing effect by means of the addition of a hydrophile group particularly ethylene oxide, or, in some instances, glycide, or perhaps a mixture of both hydrophile groups and hydrophobe groups, as, for example, in the introduction of propylene oxide along with ethylene oxide. On another type of '2 -.a material a polymeric material, such as resin, has been subjected to reaction with alkylene oxides including propylene oxide. In such instances certain derivatives obtained from polycarboxy acids have been employed. Obviously, thousands and thousands of combinations, starting with hundreds of initial water-insoluble materials, are possible. Exploration of a large number of raw materials has yielded only a few which appear to be commercially practical and competitive with available demulsifying agents.

Acyl phenol monosulfides of the kind previously described happen to be one class of suitable compound.

On the other hand, somewhat closer related products, for

instance, sulfides derived from resorcinol which has been treated with one mole of ethylene oxide so as to convert the phenolic hydroxyl to an alkylene hydroxyl and subsequently esterified, have been examined and found to be comparatively unsatisfactory as compared with the acyl phenol monosulfides herein described and an initial examination of the structure of these two types of compounds shows they have much in common. The reason or reasons for this difference is merely a matter of speculation. These acyl phenol monosulfides are comparatively expensive and obviously if a cheaper dihydroxylated emulsifier of approximately the same general characteristics would serve nothing would be gained by the employment of a more expensive raw material.

Exhaustiveoxypropylation renders a watersoluble material water-insoluble. Similarly, it renders a keroseneinsoluble material kerosene-soluble; for instance, reference has been made to the fact that this is true, for example, using polypropylene glycol 2,000. Actually, it is true with polypropylene glycol having lower molecular weights than 2,000. These materials are obtained by the oxypropylation of a water-soluble kerosene-insoluble material, i. e., either water or propyleneglycol.

Just why certain different materials which are waterinsoluble to start with, and which presumably are rendered more water-insoluble by exhaustive oxypropylation (if such expression as more water-insoluble has significance) can be converted into a valuable surfaceactive agent, and particularly a valuable demulsifying agent, by reaction with a polycarboxy acid which does not particularly affect the solubility one way or the other-depending upon the selection of the acidis unexplainable.

The new products herein described are useful for a number of purposes other than resolution of petroleum emulsions. See my co-pending application, Serial No. 267,518, filed Jan. 21, 1952.

For convenience, what is said hereinafter will be divided into four parts:

Part 1 will be concerned with the oxypropylated derivatives, i. e., diols, of the previously described acyl phenol monosulfides;

Part 2 will be concerned withthe preparation of esters from the aforementioned diols or dihydroxylated compounds;

Part 3 will be concerned with the nature of the products obtained by oxypropylation in light of the fact that certain side reactions invariably and inevitably occur, and

Part 4 will be concerned with the use of the esters obtained as described in Part 2 for the resolution of petroleum emulsions of the water-in-oil type.

PART 1 For a number of well known reasons equipment, whether laboratory size, semi-pilot plant size, pilot plant size, or large scale size, is not as a rule designed for a particular alkylene oxide. Invariably and inevitably, however, or particularly in the case of laboratory equipment and pilot plant size equipment the design is such as to use any of the customarily available alkylene oxides, i. e., ethylene oxide, propylene oxide, butylene oxide, glycide, epichlorohydrin, styrene oxide, etc. In the subsequent descriptiton of the equipment it becomes obvious that it is adapted for oxyethylation as Well as oxypropylation.

Oxypropylations are conducted under a wide variety of conditions, not only in regard to presence or absence of catalyst, and the kind of catalyst, but also in regard to the time of reaction, temperature of reaction, speed of reaction, pressure during reaction, etc. For instance, oxyalkylations can be conducted at temperatures up to approximately 200 C., with pressures in about the same 4 range up to about 200 pounds per square inch. They can be conducted, also, at temperatures approximating the boiling point of water or slightly above, as for example to C. Under such circumstances the pressure will be less than 30 pounds per square inch unless some special procedure is employed as is sometimes the case, to wit, keeping an atmosphere of inert gas such as nitrogen in the vesselduring the reaction. Such low-temperature-low-reaction rate oxypropylations have been described very completely in U. S. Patent No. 2,448,664 to H. R. Fife et al., dated September 7, 1948. Low-temperature-low-pressure oxypropylations are particularly desirable where the compound being subjected to oxypropylation contains one, two, or three points'of reaction only, such as monohydric alcohols, glycols and triols.

Since low-pressure-low-ternperature-low-reaction speed oxypropylations require considerable time, for instance, 1 to 7 days of 24 hours each to complete the reaction, they are conducted as a rule, whether on a laboratory scale, pilot plant scale, or large scale, so as to operate automatically. The prior figure of seven days applies especially to large-scale operations involving excessive oxypropylation. I have used conventional equipment with two added. automatic features:

(a) A solenoid-controlled valve which shuts off the propylene oxide in event that the temperature gets outside a predetermined and set range, for instance 95 to 120 (3., or to C., and

(b) Another solenoid valve which shuts off thepropylene oxide (or for that matter ethylene oxide if it is being used) if the pressure gets beyond a predetermined range, such as 25 to 35 pounds. Otherwise, the equipment is substantially the same as is commonly employed for this purpose where the pressure of reaction is higher, speed of reaction is higher, and time of reaction is much shorter. In such instances such automatic controls are not necessarily used.

Thus, in preparing the various examples I have found itparticularly advantageous to use laboratory equipment or pilot plant equipment which is designed to permit continuous oxyalkylation, whether it be oxypropylation or oxyethylation. With certain obvious changes the equipment can be used also to permit oxyalkylation invclving the use of glycide where no pressure isinvolved, except the vapor pressure of a solvent, if any, which may have been used as a diluent.

As previously pointed out, the method of using propylene oxide is the same as ethylene oxide. This point is emphasized only for the reason that the apparatus is so designed and constructed as to use either oxide.

The oxypropylation procedure employed in the preparation of the oxyalkylated derivatives has been uniformly the same, particularly in light of the fact that a continuous automatically-controlled procedure was employed. In this procedure the autoclave was a conventional autoclave made of stainless steel and having a capacity of approximately 15 gallons and a working pressure of one thousand pounds gauge pressure. This pressure obviously is far beyond any requirement as far as propylene oxide goes, unless there is a reaction of explosive violence involved due to accident. The autoclave was equipped with the conventional devices and openings, such as the variable-speed stirrer operating at speeds from 50 R. P. M. to 500 R. P. M.; thermometer well and thermocouple for mechanical thermometer; emptying outlet; pressure gauge; manual vent line; charge hole for initial reactants; at least one connection for introducing the alkylene oxide, such as propylene oxide or ethylene oxide, to the bottom of the autoclave; along with suitable devices for both cooling and heating the autoclave, such as a cooling'jacket, and preferably coils in addition thereto with the jacket so arranged that it is suitable for heating with steam or cooling with water and further equipped with electrical heating devices. Such autoclaves are, of course, in essence small-scale replicas of the usual conventional autoclave used in oxyalkylation procedures. Insome instances in exploratory preparations an autoclave having a smaller capacity, for instance, approximately 3 /2 liters in one case, and about 1% gallons in another case, was used.

Continuous operation, or substantially continuous operation, was achieved by the use of a separate container to hold the alkylene oxide being employed, particularly propylene oxide. In conjunction with the smaller autoclaves the container consists essentially of a laboratory bomb having a capacity of about one-half gallon, or somewhat in excess thereof. In some instances a larger bomb was used, to wit, one having a capacity of about one gallon. This bomb was equipped, also, with an inlet for charging, and an eductor tube going to the bottom of the container so as to permit discharging of alkylene oxide in the liquid phase to the autoclave. A bomb having a capacity of about 60 pounds was used in connection with the 15-gallon autoclave. Other conventional equipment consists, of course, of the rupture disc, pressure gauge, sight feed glass, thermometer connection for nitrogen for pressuring bomb, etc. The bomb was placed on a scale during use. The connections between the bomb and the autoclave were flexible stainless steel hose or tubing so that continuous weighings could be made without breaking or making any connections. This applies also to the nitrogen line, which was used to pressure the bomb reservoir. To the extent that it was required any other usual conventional procedure or addition which provided greater safety was used, of course, such as safety glass, protective screens, etc.

Attention is directed again to what has been said previously in regard to automatic controls, which shut 01f the propylene oxide in event temperature of reaction passes out of the predetermined range, or if pressure in the autoclave passes out of predetermined range.

With this particular arrangement practically all oxypropylations become uniform in that the reaction temperature was held within a few degrees of any selected point, for instance, if 130 C. was selected as the operating tem perature the maximum point would be at the most 135 C. or 138 C. and the lower point would be 125 C. or possibly 128 C. Similarly, the pressure was held at approximately 30 pounds or less within a 5-pound variation one way or the other, but might drop to practically zero, especially where no solvent such as xylene is employed. The speed of reaction was comparatively slow under such conditions as compared with oxyalkylations at 200 C. Numerous oxypropylations have been conducted in which the time varied from one day (24 hours) up to three days (72 hours), for completion of the final member of a series. In some instances the reaction involving the instant reactants may take place in considerably less time, i. e., 24 hours or less, as far as a partial oxypropylation is concerned. The minimum time recorded was about a 1 /2 hour period in a single step. Reactions indicated as being complete in 8%. hours may have been complete in a lesser period of time in light of the automatic equipment employed. This applies also where the reactions were com plete in a shorter period of time, for instance, 2 to 5 hours. In the addition of propylene oxide in the autoclave equipment as far as possible the valves were set so all the propylene oxide if fed continuously, would be added at a rate so that the predetermined amount would react within the 5 /2 hours of an 8-hour period, or two-thirds of any shorter period. This meant that if the reaction was interrupted automatically for a period of time for pressure to drop or temperature to drop, the predetermined amount of oxide would still be added in most instances well within the predetermined time period. Sometimes where the addition was a comparatively small amount in a 5-hour period there would be an unquestionable speeding up of the reaction by simply repeating the examples and using 1 /2, 2, or 3 hours instead of 5 hours.

When operating at a comparatively high temperature, for instance, between 150 and 200 C., an unreacted alkylene oxide such as propylene oxide makes its presence felt in the increase in pressure, or the consistency of a higher pressure. However, at a low enough temperature it may happen that the propylene oxide goes in as a liquid. If so, and if it remains unreacted, there is, of course, an inherent danger and appropriate steps must be taken to safeguard against this possibility; if need be, a sample must be withdrawn and examined for unreacted propylene oxide. One obvious procedure, of course, is to oxypropylate at a modestly higher temperature, for instance, at 140 to 150 C. Unreacted oxide affects determination of the acetyl or hydroxyl value of the hydroxylated compound obtained.

The higher the molecular weight of the compound, i. e., towards the latter stages of reaction, the longer the time required to add a given amount of oxide. One possible explanation is that the molecule, being larger, the opportunity for random reaction is decreased. l'nversely, the lower the molecular weight the faster the reaction takes place. For this reason, sometimes at least, increasing the concentration of the catalyst does not appreciably speed up the reaction, particularly when the product subjected to oxyalkylation has a comparatively high molecular weight. However, as has been pointed out previously, operating at a low pressure and a low temperature, even in large scale operations as much as a week or ten days time may lapse to obtain some of the higher molecular weight derivatives from monohydric or dihydric materials. Side reactions are almost invariably a problem. See U. S. Patent No. 2,236,919, dated April 1, 1941.

In a number of operations the counterbalance scale or dial scale holding the propylene oxide bomb was so set that when the predetermined amount of propylene oxide had passed into the reaction, the scale movement through a time-operating device was set for either one to two hours so that reaction continued for one to three hours after the final addition of the last propylene oxide, and thereafter the operation was shut down. This particular device is particularly suitable for use on larger equipment than laboratory size autoclaves, to wit, on semi-pilot plant or pilot plant size equipment, as well as on large scale size equipment. This final stirring period is intended to avoid the presence of unreacted oxide.

in this sort of operation, of course, the temperature range was controlled automatically by either use of cooling water, steam, or electrical heat, so as to raise or lower the temperature. The pressuring of the propylene oxide into the reaction vessel also was automatic insofar that the feed stream was set for a slow, continuous run which was shut 01f in case the pressure passed a predetermined point, as previously set out. All the points of design, construction, etc., were conventional including the gases, check valves and entire equipment. As far as I am aware at least two firms, and possibly three, specialize in autoclave equipment such as l have employed in the laboratory and are prepared to furnish equipment of this same kind. Similarly, pilot plant equipment is available. This point is simply made as a precaution in the direction of safety. Oxyalkylations, particularly involving ethylene oxide, glycide, propylene oxide, etc., should not be conducted except in equipment specifically designed for the purpose.

Example 1a The starting material was 2-butyryl-4-amyl phenol monosulfide. The particular autoclave employed was one having a maximum capacity of about 15 gallons, or approximately pounds of reaction mass. The speed of the stirrer could be varied from to 350 R' P. M. 30 pounds of the 2-butyryl-4-amyl phenol monosulfide were charged into the autoclave along with 5 pounds of finely pulverized caustic soda. No solvent was added in this particular run, although on smaller runs small amounts of xylene or other suitable solvent have been added, for instance, about one-half as much xylene as the monosulfide. Needless to say, one could add not only xylene but, for that matter, any conventional solvent. Even if the. sulfide is not completely soluble in the selected solvent, it still produces a slurry that is sometimes more convenient to handle.

The reaction pot was flushed out with nitrogen and the autoclave sealed and the automatic devices set for injecting 65 pounds of propylene oxide in approximately three hours. At the end of this time the stirring was con tinued for another half hour. The pressuring device was set for a maximum of 30 to 35 pounds per square inch. Actually in the course of the reactions due to the presence of a generous amount of catalyst the reaction pressure never exceeded the indicated maximum of 35 pounds. Experience has shown that sometimes in the initial stages the reaction takes place at a lower pressure and sometimes tends to go over the 35-pound pressure. As it happened in this particular series of oxypropylations the pressure seemed to stay within the range of 30 to 35 pounds throughout the entire series. For this reason no further reference will be made to operating pressures in the subsequent stages. Usually when one sets the gauge for a maximum pressure the bulk of the reaction can take place and quite frequently does take place at a lower pressure. Such lower pressure is the result, as a rule, of (a) Activity of the reactant,

([2) Presence of a sizeable amount of catalyst, (e) Efiicient agitation, and (d) A fairly long time of reaction.

Thepropylene oxide was-added comparatively. slowly-and, more-importanhthe selected temperature, althoughmod-ierately higher; than the boiling. pointrofzwater', was not excessivelyhigh; for instance; in this particular stage; and.

8 Whatiszsaidshereiniisspresentedtin-tabularzform in'Table 1, immediately followir'rg-zwithzsome:addediniormation asv to :rnoleculan Weight';and:.as. to solubility of i: the 1 reaction: product in water,.xylene; and kerosene.

TABLE 1' Gomppsitionbeiore. Gompositionzat end Max- Max; I Tim Phenol Oxide am Theo Phenol Oxide; Hyd 2 1 221.. hrs? sulfide, 1111117., 1 F11] I M W sulfide, amt.,.. 1 mo}, m.

lbs: lbs. Y lbs: K lb's's' Y 30. 0. 5.0. 1, 580 30.0. 65.0 5.0 1, 020 130-135 30-35. 3. 18.0 39. 0 3.0 2, 548 18: 0 74:0 3;0 1; 438" 130-135 30-35 4}? 11. 4 46. 7 L9 4,198 11. 4 84t71 12-9 I 1, 970" 130-135 30-35 6 7. 0 51. 8 1. 2.; 5,1960 740 76.8 1.- 2: 2,260 130-135 30-35- 8 45.0 3. 0 1, 604 45. 0. 55. 0. 3.0 1, 185. I 130-135 30-35. 4 27. 6 33. 6 1. 8" 2, 680 27; 6= 75. 0' 1:8 1,496 130-135 30-35 5% 8 43. 2 1. 0 4,520 15. 8 83; 2. 1. 0.. 2,1144. 130r135- -35- 7. 10.53 54. 1 0. 6 5, 900 10: 3 74.1 0.-6 2, 988- 130-135 30-85 8 50. 0- 2. 5 1, 780 50. 0 50. 0. 2. 5 1, 248. 130-135 30-35 3%- 35.4 35. 4 1. 7 2, 530 35. 4 4' 117 1, 553' -135 30-35 3%; 23. 3 4351 1. 1 3,080 23; I 7311: 1.1. 2,196." 130-135 30-35 4%. 14. 95. 46. 86' 0. 69 6, 060 14. 86.6" 69: 3,250 130-135 30-35 6t 50. 0 3. 0 1, 690 50. 0 45. 0 3. 0 1, 050 130-135 30-35 3 29. 6 26. 7 1. 7 3, 020 29. G 70. 7 1. 7 1, 470 130-135 30-35 4% l7. 4 41. 6 1. 0 4, 810 17:4 7610" 1. 0d 2, 236. 130-135. 30-35 5.

The starting material .inExamples la through .441 was 2-butyryl-4'amyl phenol .monosulfide The starting material in Examples fiathrough 8a was 2-lauroyl-4-amylphenol monosulfide.

The starting materialin Examples 9a through 12a was 2-stearoyl-4-amylphenol 'monosulfide. The starting material-in- Examples 130. through 16a was 6-stearoyl-2-amylphenolmonosulfider in, fact in. all subsequent stages, reaction toolcplace within the range of 130 to.135. C. For this reasonno further reference willbe madein Examplesla through 4a to tem: perature of reaction.

At the. completion. of the reaction asample-was takenand. oxypropylation proceeded as. in: Example. 2a,. fol.- lowing:

Example 2a 60 pounds of the reactionmass identified asExample la, preceding; monosulfide, 39-pounds-propylene oxide, and3 pounds caustic soda, were permitted-to remain in the reaction vessel. Without the addition. ofany more catalyst 39- pounds of propylene oxide-were added. The oxypropylation was conducted in the. samemanner as employed in Example 1a, preceding, particularly asfar astemperature and pressure. were concerned. The somewhat longer, to Wit, 4% .hours. This. wasduetothe fact presumably thatthe alkaliconcentration was somewhat lower. reaction mass was withdrawnas a sampleand .oxypropylation continued with the.remainder. ofithe. reaction mass:

as described. in Example 13a, following.

Example 3a 60 poundsof the reaction mass identified asExample- 2a, preceding, and ,equivalentto 11.4 pounds, of; the :original .monosulfide, 46.7 pounds of propylene oxide, and 1.9.- soda, were-permitted; to remain in -.the.

pounds of caustic reaction vessel. 38 pounds of' propylene oxide. Were.in,- troduced in the third stage. The time required. was. 6 hours. The conditions as faras' temperature. and pressure were concerned .werethe samerasdn the .PICViOllSrtWO. examples.

4a, following,

Example 4a.

of the reactionmass identified' as-Example 60 pounds and equivalent to 7.0 pounds of the mono- 3a, preceding,

sulfide and 51.8 pounds of propylene oxide, and 1.2

poundsof caustic soda, were permitted to remain in'the autoclave. Without the addition of any more causticat any stage, not only in th'is'step :but in the previoussteps, there were added 25 pounds of propylene oxide. The time required to add the oxide-was 8.hours. Conditions in regard to temperature and pressure werethe same as' in.

the preceding examples.

In this particular series ofexamples theoxypropylation'was stopped at this stage: InotherseriesI have-continned the oxypropylation so the-theoretical molecularweight was approximately 8,700to;l0,2O0.-and: the-hyT droxyl molecularweights varied .from -.-about- 3,-9O0 -to: ape proximately 4,600. Other weights, of, course; are'obtainable using the same procedure;

and-equivalent to l8-poundsofthe originalreaction time was At the end of the reaction periodpart of the After completionof thev reaction, part 1 of thereaction. mass was Withdrawn and. the remainder sub-- jected to further oxypropylationas describedin. Example- As..far. as...solubility .-.is .concerned allithe products were watervinsolubl. in. all.' stages; butwere invariably Xylene: soluble; In-the.higl ierz stages of; oxypropylation, for in: stance-,--.at ;a-hy.dtoxyl.rnolecular. weight of about- 1500 /or thereaboutsthey were. kerosene-soluble;

Ordinarily, in. the initial oxypropylation. on a. simple. compound, such as ethylene-glycol: or. propylene glycol,. the..hydi'oxyl" molecular weight isapt to approximateuthe. theoretical, molecular. weight, .based on'v completeness of reaction; it oxypropylation is.-conducted. slowly and: at. a.

comparatively, low temperature, assdescribeda In. this.

instance, however, thisadoes not seem to; follow,- as" it is 1. noted in. the preceding ,table'. that; at.- the point where: the' theoretical molecularweight is: approximately 2,000, the. hydroxyl molecular: weight is only about one-half. this:

amount. Th'isgeneralizationdoes not necessarily apply 0 Ha. CH5." H

In the" above? formulas the*-large-'-Xobviously is -not intended-to signify anything except the: central part of a large; molecule, whereas, as far as I a' speculative -explana-- tionis--concerned, one' need only consider the terminal radical-s-as sliowns Such suggestion is -of"interest only because it may-:he-awpossible; explanation of how an' in-. I crease in hydroxyl value:does-: take place '.which' could lie interpreted: as. a. decrease; in .molecular weight; This matter is considered subsequently in Part 3... For= mat ion sofi cyclio:allyleneroxidevpolymers, it not: reactive towardsspol-ycarboxy acids, presumably would. .have-the effect? fidecreasingthe: apparent :hydroxyl Valuer lnttheepresent instance-the oxypropylatedderivative was.

. acids having l8 carbon atoms.

more complex than the usual glycol or the glycol-like compound involving carbon, hydrogen and oxygen only. However, the presence of s'tlvent in the oxypropylated derivative does not detract from what has been said previously as to the general considerations involved.

The final products at the end of the oxypropylation step were somewhat viscous liquids, about as viscous as ordinary polypropylene glycols, with a dark amber tint. This color, of course, could be removed if desired by means of bleaching clays, filtering chars, or the like. The products were slightly alkaline due to the residual caustic soda. The residual basicity due to the catalyst would be the same if sodium methylate had been employed.

Needless to say, there is no complete conversion of propylene oxide into the desired hydroxylated compounds. This is indicated by the fact that the theoretical molecular weight, based on a statistical average, is greater than the molecular weight calculated by usual methods on basis of acetyl or hydroxyl value. This is true even in the case of a normal run of the kind noted previously. It is true also in regard to the oxypropylation of simple compounds, for instance, propylene glycol or ethylene glycol.

Actually, there is no completely satisfactory method for determining molecular weights of these types of compounds With a high degree of accuracy when the molecular weights exceed 2,000. In some instances the acetyl value or hydroxyl value serves as satisfactorily as an index to the molecular weight as any other procedure, subject to the above limitations, and especially in the higher molecu lar weight range. If any difliculty is encountered in the manufacture of the esters, as described in Part 2, the stoichiometrical amount of acid or acid compound should be taken which corresponds to the indicated acetyl or hydroxyl value. This matter has been discussed in the literature and is a matter of common knowledge and requires no further elaboration. In fact, it is illustrated by some of the examples appearing in the patent previously mentioned.

PART 2 As previously pointed out, the present invention is concorned with acidic esters obtained from the oxypropylated derivatives described in Part I, preceding, and polycarboxy acids, particularly tricarboxy acids like citric, and dicarboxy acids such as adipic acid, phthalic acid, or anhydride, succinic acid, diglycollic acid, sebacic acid, azelaic acid, aconitic acid, maleic acid, or anhydride, citraconic acid or anhydride, maleic acid or anhydride adducts, as obtained by the Diels-Alder reaction from products such as maleic anhydride, and cyclopentadiene. Such acids should be heat-stable so they are not decomposed during esterification. They may contain as many as 36 carbon atoms as, for example, the acids obtained by dimerization of unsaturated fatty acids, unsaturated monocarboxy fatty acids, or unsaturated monocarboxy Reference to the acid in the hereto appended claims obviously includes the anhydrides or any other obvious equivalents. My preference, however, is to use polycarboxy acids having not over 8 carbon atoms.

The production of esters including acid esters (fractional esters) from polycarboxy acids and glycols, or other hydroxylated compounds, is Well known. Needless to say, various compounds may be used such as the low molal ester. the anhydride, the acyl chloride, etc. However, for purpose of economy it is customary to use either the acid or the anhydride. A conventional procedure is employed. On a laboratory scale one can employ a resin pot of the kind described in U. S. Patent No. 2,499,370,

dated March 7, 1950, to DeGroote and Keiser, and particularly with one more opening to permit the use of a porous spreader if hydrochloric acid gas is used as a catalyst. Such device or absorption spreader consists of minute alundum thimbles which are connected to a gas tube. One can add a sulfonic acid such as paratoluene sulfonic acid as a catalyst. There is some objection to this because in some instances there is some evidence that this acid catalyst tends to decompose or rearrange heat-oxypronylated compounds. it is particularly likely to do so if the esterification temperature is too high. in the case of polycarboxy acids such as diglycollic acid which is strongly acidic there is no need to add any catalyst. The use of hydrochloric acid gas has one advantage over paratoluene sulfonic acid and that is that at the end of the reaction it can be removed by flushing out with nitrogen, whereas there is no reasonably convenient means available of removing the paratoluene sulfonic acid or other sulfonic acid employed. If hydrochloric acid is employed one need only pass the gas through at an exceedingly slow rate so as to keep the reaction mass acidic. Only a trace of acid need be present. I have employed hydrochloric acid gas or the aqueous acid itself to eliminate the initial basic material. My preference, however, 15 to use no catalyst whatsover and to insure complete dryness of the diol, as described in the final procedure just preceding Table 2.

The products obtained in Part 1, preceding, may contain a basic catalyst. As a general procedure, I have added an amount of half-concentrated hydrochloric acid considerably in excess of what is required to neutralize the residual catalyst. The mixture is shaken thoroughly and allowed to stand overnight. It is then filtered and refluxed with the xylene present until the Water can be separated in a phase-separating trap. As soon as the product is substantially free from water the distillation stops. This preliminary step can be carried out in the flask to be used for esterification. If there is any further deposition of sodium chloride during the reflux stage, needless to say, a second filtration may be required. In any event, the neutral or slightly acidic solution of the oxypropylated derivatives described in Part 1 is then diluted further with sufficient xylene, decalin, petroleum solvent, or the like, so that one has obtained approximateiy a 45%65% solution. To this solution there is added a polycarboxylated reactant, as previously described, such as phthalic anhydride, succinic acid, or anhydride, diglycollic acid, etc. The mixture is refluxed until esterification is complete, as indicated by elimination of Water or drop in carboxyl value. Needless to say, if one produces a half-ester from an anhydride such as phthalic anhydride, no water is eliminated. However, if it is obtained from diglycollic acid, for example, Water is eliminated. All such procedures are conventional and have been so thoroughly described in the literature that further consideration will be limited to a few examples and a comprehensive table.

Other procedures for eliminating the basic residual catalyst, if any, can be employed. For example, the oxyalkylation can be conducted in absence of a solvent or the solvent removed after oxypropylation. Such oxypropylation end-product can then be acidified with just enough concentrated hydrochloric acid to just neutralize the residual basic catalyst. To this product one can then add a small amount of anhydrous sodium sulfate (sufficient in quantity to take up any water that is present) and then subject the mass to centrifugal force so as to eliminate the hydrated sodium sulfate and probably the sodium chloride formed. The clear, somewhat viscous, straw-colored amber liquid so obtained may contain a small amount of sodium sulfate or sodium chloride, but in any event is perfectly acceptable for esterification in the manner described.

ft is to be pointed out that the products here described are not polyesters in the sense that there is a plurality of both diol radicals and acid radicals; the product is characterized by having only one diol radical.

In some instances and, in fact. in many instances, I have found that in spite of the dehydration methods em loyed above, a mere trace of water still comes through. and that this mere trace of water certainly interferes with the acetyl or hydroxyl value determination, at least when a number of conventional procedures are used and may retard esterification. particularly where there is no sulfonic acid or hydrochloric acid present as a catalyst. Therefore, l have preferred to use the following procedure: I have employed about 200 grams of the diol compound, as described in Part l, preceding; I have added about 60 grams of benzene and refluxed this mixture in the glass resin pot, using a phase-separating trap, until the benzene carried out all the water present as water of solution or the equivalent. Ordinarily this refluxing temperature is apt to be in the neighborhood of C. to possibly C. When all this water or moisture has been removed I also withdraw approximately 20 grams, or a little less, benzene and then add the required amount of the carboxy reactant and also about 150 grams of a highboiling aromatic petroleum solvent. These solvents are sold by various oil refineries and, as far as solvent effect TABLE 3 Art Maximum Time of Ex. No. of Solvent solesterifiesterifi- 2 391d ester vent cation cation (cc (grs.) temp, 0. (hrs) 1b Xylene, solvent 7.. 626 160-165 6 18 2 ----do 648 175-180 6 608 145-150 4 582 170-175 7 54 417 160-170 6 9 433 170-180 6 408 140-145 5 437 170-175 6 550 170-175 6 566 165-175 6 542 145-150 5 570 170-175 6 623 170-175 8 639 170-175 8 614 145-150 5 612 170-175 8 9 708 170-175 4 18 740 170-175 4 690 145-150 4 766 170-175 4 18 432 170-175 5% 9 448 170-175 6 423 150-160 5 452 170-175 8 9 569 170-175 5 9 585 170-175 6 560 145-150 5 547 170-175 8 27 402 170-175 6 4. 5 410 170-175 6 397 130-140 6 398 170-175 9 4. 5 370 160-165 4 9 386 170-175 4 361 130-140 4 359 170-175 4 9 447 150-160 4% 9 463 155-160 5 438 130-140 4 439 150-155 6 9 303 150-160 5 4. 5 311 165-170 5 318 130-135 4% 299 150-160 7 4. 5 348 150-155 8 3. 6 348 130-135 5 355 150-160 8 339 150-155 8 10. 3 640 160-165 6 18 673 160-165 6 680 160-165 6 18 620 160-165 6 18 425 160-170 8 9 438 160-170 8 445 160-170 9 414 160-170 8 9 309 160-170 8 4. 5 317 160-170 8 319 160-170 8 4. 5 304 160-170 8 4. 5 386 165-180 8 4. 5 394 160-170 9 396 150-160 8 4. 5 380 155-160 10 4. 5

The procedure for manufacturing the esters has been illustrated by preceding examples. If for any reason reaction does not take place in a manner that is acceptable, attention should be directed to the following details:

(a) Recheck the hydroxyl or acetyl value of the oxypropylated high molal glycol as in Part 1, preceding;

(b) If the reaction does not proceed with reasonable speed, either raise the temperature indicated or else extend the period of time up to 12 or 16 hours if need be;

(c) If necessary, use /2 of paratoluene sulfonic acid, or some other acid, as a catalyst; and

(d) If the esterification does not produce a clear product, a check should be made to see if an inorganic salt such as sodium chloride or sodium sulfate is not precipitating out. Such salt should be eliminated, at least for exploration experimentation, and can be removed by filtering.

Everything else being equal, as the size of the molecule increases and the reactive hydroxyl radical represents a smaller fraction of the entire molecule, more difficulty is involved in obtaining complete esterification.

Even under the most carefully controlled conditions of oxypropylation involving comparatively low temperatures and long time of reaction, there are formed certain compounds whose compositions are still obscure. Such side reaction products can contribute a substantial proportion of the final cogeneric reaction mixture. Various suggestions have been made as to the nature of these compounds, such as being cyclic polymers of propylene oxide, dehydration products with the appearance of a vinyl radical, or isomers of propylene oxide or derivatives thereof, i. e., of an aldehyde, ketone, or allyl alcohol. In some instances an attempt to react the stoichiometric amount of a polycarboxy acid with the oxypropylated derivative results in an excess of the carboxylated reactant, for the reason that apparently under conditions of reaction less reactive hydroxyl radicals are present than indicated by the hydroxyl value. Under such circumstances there is simply a residue of the carboxylic reactant which can be removed by filtration, or, if desired, the esterification procedure can be repeated, using an appropriately reduced ratio of carboxylic reactant.

Even the determination of the hydroxyl value and conventional procedure leaves much to be edsired, due either to the cogeneric materials previously referred to, or, for that matter, the presence of any inorganic salts or propylene oxide. Obviously this oxide should be eliminated.

The solvent employed, if any, can be removed from the finished ester by distillation, and particularly vacuum distillation. The final products or liquids are generally from almost black or reddishblack to dark amber in color, and show moderate viscosity. They can be bleached with bleaching clays, filtering chars, and the like. However, for the purpose of demulsification or the like, color is not a factor and decolorization is not justified.

In the above instances I have permitted the solvents to remain present in the final reaction mass. In other instances I have followed the same procedure, using decalin or a mixture of decalin or benzene in the same manner and ultimately removed all the solvents by vaccuum distillation.

PART 3 In the hereto appended claims the demulsifying agent is described as an ester obtained from a polyhydroxylated material prepared from the described diols. If one were concerned with a monohydroxylated material or a dihydroxylated material one might be able to write a formula which in essence would represent the particular product. However, in a more highly hydroxylated ma terial the problem becomes increasingly more difficult for reasons which have already been indicated in connection with oxypropylation and which can be examined by merely colnsidering for the moment a monohydroxylated materia Oxyalkylation, particularly in any procedure which involves the introduction of repetitious ether linkages, i. e., excessive Oxyalkylation, using, for example, ethylene oxide, propylene oxide, etc., runs into difficulties of at least two kinds; (a) formation of a cogeneric mixture rather than a single compound, and (b) excessive side reactions or the like. The former phase will be considered in the paragraphs following. As to the latter phase, see U. S. Patent No. 2,236,919, dated April 1, 1941, to Reynhart.

Oxypropylation involves the same sort of variations as appear in preparing high molal polypropylene glycols. Propylene glycol has a secondary alcoholic radical and a primary alcohol radical. Obviously then polypropylene glycols could be obtained, at least theoretically, in which two secondary alcoholic groups are united or a secondary alcohol group is united to a primary alcohol group, etherization being involved, of course, in each instance. Needless to say, the same situation applies when one has oxyproplated polyhydric materials having 4 or more hydroxyls, or the obvious equivalent.

Usually no effort is made to differentiate between oxypropylation taking place, for example, at the primary alcohol radical or the secondary alcohol radical. Actually, when such products are obtained, such as a high molal propylene glycol or the products obtained in the manner herein described one does not obtain a single derivative such as HO(RO)71.H or -(RO)nI-I in which n has one and only one value, for instance, l4, 15 or 16, or the like. Rather, one obtains a cogeneric mixture of closely related or touching homologues. These materials invariably have high molecular weights, and cannot be separated from one another by any known procedure, without decomposition. The proportion of such mixture represents the contribution of the various individual members of the mixture. On a statistical basis, of course, 11 can be appropriately specified. For practical purposes one need only consider the oxypropylation of a monohydric alcohol because in essence this is substantially the mechanism 1 5 involved. iEveninc-such'instances where :one. isconcerned with a'monohydric :reactant .one cannot draw a single :formula :and say that by following "such ,procedure one :can readily'obtain '80% :or 90% or 100% of such com- :pound. THowever, in the case-ofattleastrnonohydric ini- 'tial'reactants'one canreadily drawzthe formulas of a large number of compounds which appearin some of the proba'ble zmixtures or can be prepared as :components and mixtures which are manufactured conventionally.

Sirnply'by way of :illustration reference iszmade to U. S. Patent No. 2549;434, datedApril 17, 1951,?toDeGroote, 'Wirtel and 'Pettingill.

:I-Iowever, momentarily referring again to;a monohydric initial reactant it is obvious that if :one selects any such simple hydroxylated compound .andsubjects such com- :pound to -oxyalkylation, :such :as oxyethylation, or oxy- 'propylation, itibecomes apparent that one is really pro- :ducinga polymerof the alkylene .oxide'except'for-the terminaligroup. This is particularly true where the amount of "oxide added 'is comparatively large, .20, :30, '40 or i50 units. If such compound is subjected to oxyethylation 'so 'as to introduce units of ethylene "oxide, :it is well'known that one :doesnot'obtain a single constituent which, for the sake of convenience, may be indicated as RO(C2"H4O)30OH. Elnstead, one obtains a .cogerreric'mixture of closely .related homologues in*which the formula may be shown as the following:

'RO (Cal-I40) 11H wherein n, as farm; 'the statistical average goes, is 30, but the'individualrmembers present insignificant amount rmay=varyfrom instances where n has a'valueof 25, and perhaps less, to a point where n may represent or more. Such mixture is, as stated, a-cogeneric closely related series of touching homologous compounds. Considerable investigation has been made in regard to .the distribution curves forlinear polymers. Attention is directed to the article entitled Fundamental Principles of Condensation Polymerization, by Flory, which appeared in Chemical Reviews, volume 39, No. 1, page 137.

'Unfortunately, as has been pointed out by Flory and other investigators, there is no satisfactory method, based on either experimental or mathematical examination, of indicating the exact proportion of the various members of touching-homologous series which appear in cogeneric condensation products of the kind described. This means that from the practical standpoint, i. e., the ability to describe how to make 'the product under consideration and how to repeat such production time after time without difiiculty, it is necessary to resort to some other method of descrlptionyor else consider the value of n, in formulas such as those which have appearedpreviously and which appear in the-claims, as representing both individual constituents in which n has a single definite value, and also with the understanding that n represents the average statistical value based on the assumption of completeness of;reaction.

This may be illustrated as follows: Assume that in any particular example the molal ratio of propylene oxide ,per hydroxyl is .15 -to 1. In a generic formula 15 to 1 could be 10, 20, or some other amount and indicated by n. 'Referring-to this specific case actually one obtains products in which n probably varies from 10 to 20, perhaps even further. The average value, however, is 15, assuming, as previously stated, that the reaction is complete. The product shown by the formula is perhaps best describedalso in terms of method of manufacture.

It becomes obvious that when carboxylic acidic esters are prepared from such high molal molecular weight materials that the ultimate esterification product must, in turn, be a cogeneric mixture. Likewise, it is obvious that the contribution to the total molecular weight made by the 'polycarboxy reactant is small. Thus, one might expectthat the efiectiveness of the demulsifier in the form of the acidicfractional ester would be comparable to the esterified hydroxylated material. Remarkably enough, in practically every instance the product is distinctly better, andin the majority of instances much more effective.

PART 4 Conventional .demulsifying agents employed in the treatment of oilfield emulsions are used as such, or after dilution withany suitable solvent, such as water, petroleum hydrocarbons, such as benzene, toluene, xylene, tar acid .oil, cresol, anthracene oil, etc. Alcohols, particufor instance, 10,

of demulsification procedure to recover clean-oil.

larly aliphatic alcohols, such as methyl alcohol, ethyl alcohol, vdenaturedalcohol, .propyl alcohol, butyl alcohol, hexyl alcohol, octyl alcohol, etc., may be employed as diluents. Miscellaneous solvents such as pine oil, carbon .tetrachloride, sulfur dioxide extract obtained'in the refining of petroleum, etc., may be employed as diluents. Similarly, the material or materials employed as the demulsifying :agent-of my process'rnay'be admixed with one or more of the solvents customarily used sin connection with conventional demulsifying agents. Moreover, said material or materials may -be used alone-or in admixture with other suitable well-known classes of demulsifying agents.

It is well known that conventional demulsifying agents may be used ina water-soluble form, orin'anloil-soluble form, or in a form exhibiting both .oiland watersolubility. Sometimes they may be used in a form which exhibits relatively limited oil-solubility. However, since such reagents are frequently used in a ratio of 1 to 10,000 or 1 to 20,000, or 1 to 30,000, or even 1 lto 40,000, or 1 to 50,000 as in desaltingpractice, such'an apparent insolubility in oil and water 'is not significant because said reagents undoubtedly have solubility within such concentrations. This same fact is true in regard to -the material or materials employed as the demulsifying agent of my process.

In practicing -my process for resolving petroleum emulsions of the water-in-oil type, a treating agent or demulsifying agent of the kind above described'is brought into contact with or cause to act upon .the emulsion .to be treated, in any of the various apparatusnow generally used to resolve or break petroleum emulsions with a chemical reagent, the above procedure being used alone or in combination with other demulsifying iprocedure, such as the electrical dehydration process.

One type of procedure .is to accumulate a volumetof emulsified oil in a tank andconduct a batchtreatment type In this procedure the emulsion is admixed with the .demulsifier, for example by agitating the tank of emulsion and slowly dripping demulsifier into the emulsion. In some cases mixing is achieved'by heating the emulsion while dripping'in the demulsifier, depending upon the convection currents in the emulsion to produce satisfactory admixture. In a third modification of this'type of treatment, a circulating pump withdraws emulsion from, e. 'g., the bottom of the tank, and reintroduces it into the top ofthe tank, thedemulsifier bein'g'added, for example, .at the suction sideof said-circulating pump.

In asecond type of treating procedure, the desmulsifier is introduced into the well fluids at the well-head or :at some point between the well-head and the final oil storage tank, by means of an adjustable proportioningrnehanism or proportioning pump. Ordinarily the flow of r fluids through the subsequent lines and .-fittings suffices to produce the desired degree of mixing of demulsifier and emulsion, although in some instances additionalmixing devicesmay be introduced into the flow system. In this general procedure, the system may include various mechanical devices for withdrawing free water, separating entrained water, or accomplishing quiscent settling of the chemicalized emulsion. Heating devices -may -.likewise be incorporated in any of the treating procedures described herein.

A third type of application (down-the-hole) :of demulsifier to emulsion is to introduce the'demulsifierl either periodically or continuously'inidiluted or undiluted form into the well and to allow it to come to the surface with the well fluids, and then to flow the chemicalized emulsion through any desirable surface equipment, such as employed in the other treating procedures. This :particular type of application is decidedlyuseful when the=demulsifier is used in connection with acidification ofcacareous oil-bearing strata, especially if suspended in or dissolved in the acid employed for acidification.

In all cases, it will be .apparent from the foregoing description, the broad process consists simply in introducing a relatively small proportion of demulsifier into a relatively large proportion of emulsion, admixing the chemical and emulsion either through natural flow or through special apparatus, with or "without the application of heat, and'allowingvthe mixture tostand quiescent until the undesirable water content of 'the emulsion-separates and settles from the mass.

The .following .is a atypical installation.

A reservoir to hold the demulsifier of the kind described (diluted or undiluted) is placed at the well-head where the eifiuent liquids leave the Well. This reservoir or container, which may vary from gallons to 50 gallons for convenience, is connected to a proportioning pump which injects the demulsifier drop-Wise into the fluids leaving the well. Such chemicalized fluids pass through the floW- line into a settling tank. The settling tank consists of a tank of any convenient size, for instance, one which will hold amounts of fluid produced in 4 to 24 hours (500 barrels to 2000 barrels capacity), and in which there is a perpendicular conduit from the top of the tank to almost the very bottom so as to permit the incoming fluids to pass from the top of the settling tank to the bottom, so that such incoming fluids do not disturb 'stratification Which takes place during the course of demulsification: The settling tank has two outlets, one being below the water level to drain ofi the water resulting from demulsification or accompanying the emulsion as free Water, the other being an oil outlet at the top to permit the passage of dehydrated oil to a second tank, being a storage tank, which holds pipeline or dehydrated oil. If desired, the conduit or pipe which serves to carry the fluids from the Well to the settling tank may include a section of pipe with baffles to serve as a mixer, to insure thorough distribution of the demulsifier throughout the fluids, or a heater for raising the temperature of the fluids to some convenient temperature, for instance, 120 to 160 F., or both heater and mixer.

Demulsification procedure is started by simply setting the pump so as to feed a comparatively large ratio of demulsifier, for instance, 1:5,000. As soon as a complete break or satisfactory demulsification is obtained, the pump is regulated until experience shows that the amount of demulsifier being added is just suflicient to produce clean or dehydrated oil. The amount being fed at such stage is usually 1:l0,000, 1:l5,000, l:20,000, or

the like.

In many instances the oxyalkylated products herein specified as demulsifiers can be conveniently used without dilution. However, as previously noted, they may be diluted as desired with any suitable solvent. For instance, by mixing 75 parts by Weight of an oxyalkylated derivative, for example, the product of Example 13b with 15 parts by weight of xylene and parts by weight of isopropyl alcohol, an excellent demulsifier is obtained. Selection of the solvent will vary, depending upon the solubility characteristics of the oxyalkylated product, and of course will be dictated in part by economic considerations, i. e., cost.

As noted above, the products herein be used not only in diluted form, but also may be used admixed with some other chemical demulsifier. A mixture which illustrates such combination is the following:

Oxyalkylated derivative, for example, the product of Example 13b, 20%;

A cyclohexylamine salt of a polypropylated naphthalene monosulfonic acid, 24%;

An ammonium salt of a polypropylated naphthalene monosulfonic acid, 24%;

A sodium salt of oil-soluble mahogany petroleum sulfonic acid, 12%;

A high-boiling aromatic petroleum solvent,

Isopropyl alcohol, 5%.

The above proportions are all weight percents.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. A process for breaking petroleum emulsions of the water-in-oil type characterized by subjecting the emulsion to the action of a demulsifier including hydrophile synthetic products; said hydrophile synthetic products being characterized by the following formula:

described may in which n is a Whole number not over 2, and in which 18 is the divalent radical obtained by theremoval of the phenolic hydrogen atoms from an acyl phenol monosulfide of the formula 0 OH HO coon in which n" has its previous significance; and with the final proviso that both the initial monosulfide and the parent dihydroxylated compound prior to esterification be water-insoluble.

2. A process for breaking petroleum emulsions of the Water-in-oil type characterized by subjecting the emulsion to the action of a demulsifier including hydrophile synthetic products; said hydrophile synthetic products being characterized by the following formula:

in which n" is a Whole number not over 2, and in which is the divalent radical obtained by the removal of the phenolic hydrogen atoms from an acyl phenol monosulfide of the formula l 1 R1 R2 in which R1 and R2 are alkyl groups having 1 to 20 carbon atoms and R3 and R4 are alkyl radicals; n and 11' represent whole numbers which when added together equal a sum varying from 15 to 80, and R is the carbonlinked radical of a polycarboxy acid selected from the groip consisting of acyclic and isocyclic polycarboxy acl s COOH in which n" has its previous significance; and with the final proviso that both the initial monosulfide and the parent dihydroxylated compound prior to esterification be water-insoluble.

3. A process for breaking petroleum emulsions of the water-in-oil type characterized by subjecting the emulsion to the action of a demulsifier including hydrophile synthetic products; said hydrophile synthetic products being characterized by the following formula:

0 I II RO (CaHaO),uGR(CO 011),."

in which n" is a whole number not over 2, and in which is the divalent radical obtained by the removal of the phenolic hydrogen atoms from an acyl phenol monosulfide of the formula OH HO O in which R1 and R2 are alkyl groups having 1 to 20 carbon atoms and R3 and R4 are identical alkyl radicals; n and n represent whole numbers which when added together equal a sum varying from to 80, and R is the carbon-linked radical of a polycarboxy acid selected from thedgroup consisting of acyclic and isocyclic polycarboxy an s COOH (COOHM in which n" has its previous significance; and with the final proviso that both the initial monosulfide and the parent dihydroxylated compound prior to esterification be water-insoluble.

4. A process for breaking petroleum emulsions of the water-in-oil type characterized by subjecting the emulsion to the action of a demulsifier including hydrophile synthetic products; said hydrophile synthetic products being characterized by the following formula:

II l v-o (CaHaO),.CR(C 0 011), s

in which n" is a whole number not over 2, and in which s li e is the divalent radical obtained by the removal of the phenolic hydrogen atoms from an acyl phenol monosulfide of the formula 0 OH HO RaC- S in which R1 and R2 are alkyl groups having 1 to carbon atoms and R3 and R4 are identical alkyl radicals having at least 7 and not over carbon atoms; n and n represent whole numbers which when added together equal a sum varying from 15 to 80, and R is the carbonlinked radical of a polycarboxy acid selected from the grolp consisting of acyclic and isocyclic polycarboxy ac1 s COOH in which n" has its previous significance; and with the final proviso that both the initial monosulfide and the parent dihydroxylated compound prior to esterification be water-insoluble.

5. A process for breaking petroleum emulsions of the water-in-oil type characterized by subjecting the emulsion to the action of a demulsifier including hy-= 20 drophile synthetic products; said hydrophile synthetic products being characterized by the following formula:

0 I I R"O(C3H5O)I4JR(CO011).." in which n is a Whole number not over 2, and in which r S so is the divalent radical obtained by the removal of the phenolic hydrogen atoms from an acyl phenol monosulfide of the formula 0 O H HO O a II Rs- S CR4 in which R1 and R2 are alkyl groups having 4 to 14 carbon atoms and R3 and R4 are identical alkyl radicals having at least 7 and not over 21 carbon atoms; 11 and n represent whole numbers which when added together equal a sum varying from 15 to 80, and R is the carbon-linked radical of a polycarboxy acid selected from the group consisting of acyclic and isocyclic polycarboxy acids coon 0 R O(CSHGO)n R(COOH)n" O 1 %"O(CaHaO)n' R(COOH)" in which n" is a whole number not over 2, and in which is the divalent radical obtained by the removal of the phenolic hydrogen atoms from an acyl phenol monosulfide of the formula OH Badg s-ORR. 381 2 in which R1 and R2 are alkyl groups having 4 to 14 carbon atoms and R3 and R4 are identical alkyl radicals having at least 7 and not over 21 carbon atoms; n and n represent whole numbers which when added together equal a sum varying from 15 to 80, and R is the carbonlinked radical of a polycarboxy acid selected from the grotilip consisting of acyclic and isocyclic polycarboxy acl s COOH in which n" has its previous significance; said polycarboxy acid having not over 8 carbon atoms; and with the final proviso that both the initial monosulfide and the parent dihydroxylated compound prior to esterification be water-insoluble.

7. A process for breaking petroleum emulsions of the water-in-oil type characterized by subjecting the emulsion to the action of demulsifier including hydrophile synthetic products; said hydrophile synthetic products being characterized by the following formula:

1 lo o in which R1 and R2 are alkyl groups having 4 to 14 carbon atoms and R3 and R4 are identical alkyl radicals having at least 7 and not over 21 carbon atoms; n and n represent whole numbers which when added together /COOH COOH said dicarboxy acids having not over 8 carbon atoms; and with the final proviso that both the initial monosulfide and the parent dihydroxylated compound prior to esterification be water-insoluble.

8d. The process of claim 7 in which the acid is phthalic aci 9d. The process of claim 7 in which the acid is maleic aci 10. The process of claim 7 in which the acid is diglycolic acid.

111. The process of claim 7 in which the acid is oxalic aci 12. The process of claim 7 in which the acid is succinic acid.

References Cited in the file of this patent UNITED STATES PATENTS Number 

1. A PROCESS FOR BREAKING PETROLEUM EMULSION OF THE WATER-IN-OIL TYPE CHARACTERIZED BY SUBJECTING THE EMULSION TO THE ACTION OF A DEMULSIFIER INCLUDING HYDROPHILE SYNTHETIC PRODUCTS; SAID HYDROPHILE SYNTHETIC PRODUCTS BEING CHARACTERIZED BY THE FOLLOWING FORMULA: 